From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from auth.b.painless.aa.net.uk (b.painless.aa.net.uk [IPv6:2001:8b0:0:30::51bb:1e34]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by huchra.bufferbloat.net (Postfix) with ESMTPS id 5C409208AA0 for ; Sat, 16 Jun 2012 02:54:12 -0700 (PDT) Received: from d.5.3.f.4.2.4.f.4.e.7.5.5.8.0.0.1.0.0.0.d.9.f.f.0.b.8.0.1.0.0.2.ip6.arpa ([2001:8b0:ff9d:1:85:57e4:f424:f35d]) by b.painless.aa.net.uk with esmtps (TLSv1:AES128-SHA:128) (Exim 4.72) (envelope-from ) id 1Sfphf-0000Qv-O0 for cerowrt-devel@lists.bufferbloat.net; Sat, 16 Jun 2012 10:53:59 +0100 From: Alexander Hulse Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Date: Sat, 16 Jun 2012 10:53:58 +0100 Message-Id: To: cerowrt-devel@lists.bufferbloat.net Mime-Version: 1.0 (Apple Message framework v1278) X-Mailer: Apple Mail (2.1278) Subject: [Cerowrt-devel] Baby jumbo frames support? X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 16 Jun 2012 09:54:17 -0000 I've done some basic research and some (unsuccessful) hacking the on the = driver source for the ag71xx driver and was wondering about baby jumbo = frame support? I know that the WNDR37/800's built in switch supports passing jumbo = frames, but the underlying router interfaces do not support large MTU = frames. However, this: = http://wiki.mikrotik.com/wiki/Manual:Maximum_Transmission_Unit_on_RouterBo= ards seems to imply that the built-in interfaces ought to support baby jumbo = frames, unless I'm misunderstanding what they are saying. As to the "Why?", in the UK, the fibre offering by BT using FTTC uses a = PPPoE modem that can understand PPPoE packets with an MTU 1508, as = described in RFC 4638. It was possible using a Netgear WNR834T with the application of some = patches from the pppd git: = http://git.ozlabs.org/?p=3Dppp.git;a=3Dcommit;h=3Dfd1dcdf758418f040da3ed80= 1ab001b5e46854e7 http://wiki.aa.net.uk/index.php/FTTC_Modem Would this be a useful feature to add (if possible) to CeroWrt so that = full sized frames can be used if the ISP / connection supports it? Alex=